Known barrel retaining structures of this type are generally provided with a locking element and have been employed to make the connection between the firearm barrel placed in a breech and the stock of the pistol. In addition, there is generally an operating connection between the firing pin also disposed in the breech and a trigger arm located in the pistol stock and connected to the trigger. In order to disassemble the pistol, it is necessary to unlock these connections in order to enable the breech together with the barrel to be separated from the stock.
In DE-OS 22 46 346 there is disclosed an automatic pistol in which the barrel is provided with a downwardly-oriented hook that interacts with a control pin to unlock the connection between the barrel and the breech. On the front side of the barrel hook, there is a blocking nose that is engageable against the transversely positioned blocking bolt which is pivotally mounted in t he stock and prevents a further forward movement of the barrel and breech. The blocking bolt which is circular in cross section has a milled actuating surface such that in a particular torsional or pivoting position will release the blocking nose such that during a disassembly of the pistol the breech and barrel can be removed from the guide mechanism of the front portion of the stock. Initially, the breech is moved into its rearmost position against the force of the breech spring. Then the blocking bolt is pivoted into the unblocking position by means of an actuating element located on the outside of the pistol and connected to the blocking bolt. The breech is now released and can be moved forwardly so as to be separated from the stock.
In order to ensure that the cocked breech is not unintentionally propelled forwardly, the actuation element is automatically coupled with the breech catch device and is generally actuated by the empty magazine after the last cartridge has been fired. This will maintain the breech in the open position. As long as the disassembly lever is maintained in its actuated position, the breech catch device will remain in the catch position. When the disassambly lever is released, the breech catch under the action of a return spring will move into the release position so that the breech can be removed from the forward portion of the stock.
This prior art structure has the disadvantage that in order to disassemble the pistol, the breech must be pulled back manually against the force of its return spring and simultaneously, the blocking lever must be actuated. This actuation is complicated, time-consuming and requires a considerable amount of strength. Further, the coupling with the breech catch requires a relatively complex and expensive construction.